Spherical Map a Pattern with Perfect Tiling - Possible?

[JGary]

Is there a easy way to map a repeating pattern onto a sphere with without getting pinching/distortion at the poles? The patterns I need to repeat have to be continous and interlocking (ie. camoflage).

I've done some searching on the internet and did come across a couple of ways, however you either get a seam at the back or a extra nasty looking south pole. I can use one of these methods as a starting point, but a lot of work will be involved cleaning up the bad areas.

http://www.thebest3d.com/dogwaffle/lua/polar/index.html

http://www.brothersoft.com/spherical-mapping-corrector-download-168999.html

http://tinyurl.com/6mum6p

[clagman]

I've always gone the route of polar coordinates and 180º canvas. Leaves a simple seam that's easily cleaned up. If you are using photoshop you copy the original layer do the PC filter, and use the circular marque (with feather) to draw around the pinched area. Use the selection to sample the undistorted layer and paste the result into the distorted layer, then do polar to rectangular coords. Flip the canvas 180 and do the same thing for the other pole. This leaves a seam which you brush out with clone stamp, patch, healing brush, or drawing tools etc. You could probably do just as well or better using UV mapping for that job and leave the image undistorted aside from the mods to make it tile.